Bartonella henselae inhibits apoptosis in Mono Mac 6 cells
Article first published online: 20 AUG 2004
Volume 7, Issue 1, pages 91–104, January 2005
How to Cite
Kempf, V. A. J., Schairer, A., Neumann, D., Grassl, G. A., Lauber, K., Lebiedziejewski, M., Schaller, M., Kyme, P., Wesselborg, S. and Autenrieth, I. B. (2005), Bartonella henselae inhibits apoptosis in Mono Mac 6 cells. Cellular Microbiology, 7: 91–104. doi: 10.1111/j.1462-5822.2004.00440.x
- Issue published online: 20 AUG 2004
- Article first published online: 20 AUG 2004
- Received 24 April, 2004; revised 6 July, 2004; accepted 7 July, 2004.
Bartonella henselae causes the vasculoproliferative disorders bacillary angiomatosis and peliosis probably resulting from the release of vasculoendothelial growth factor (VEGF) from infected epithelial or monocytic host cells. Here we demonstrate that B. henselae in addition to VEGF induction was also capable of inhibiting the endogenous sucide programme of monocytic host cells. Our results show that B. henselae inhibits pyrrolidine dithiocarbamate (PDTC)-induced apoptosis in Mono Mac 6 cells. B. henselae was observed to be present in a vacuolic compartment of Mono Mac 6 cells. Direct contact of B. henselae with Mono Mac 6 cells was crucial for inhibition of apoptosis as shown by the use of a two-chamber model. Inhibition of apoptosis was paralleled by diminished caspase-3 activity which was significantly reduced in PDTC-stimulated and B. henselae-infected cells. The anti-apoptotic effect of B. henselae was accompanied by (i) the activation of the transcription factor NF-κB and (ii) the induction of cellular inhibitor of apoptosis proteins-1 and -2 (cIAP-1, -2). Our results suggest a new synergistic mechanism in B. henselae pathogenicity by (i) inhibition of host cell apoptosis via activation of NF-κB and (ii) induction of host cell VEGF secretion.